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authorSimon-Kor <52245124+Simon-Kor@users.noreply.github.com>2024-05-28 15:33:45 +0200
committerSimon-Kor <52245124+Simon-Kor@users.noreply.github.com>2024-05-28 15:33:45 +0200
commitecfb1a66f2159e078199e54edf8a80004c28195a (patch)
tree86b01994a00159189938904850d879d893c0a7a6 /library/topology/metric-space.tex
parentd7ba30d2bd4ecf87e4b962d2b9f2555fb7d59d1d (diff)
proofing some lammes about topological basis
Diffstat (limited to 'library/topology/metric-space.tex')
-rw-r--r--library/topology/metric-space.tex60
1 files changed, 39 insertions, 21 deletions
diff --git a/library/topology/metric-space.tex b/library/topology/metric-space.tex
index 8ec83f7..1c6a0ca 100644
--- a/library/topology/metric-space.tex
+++ b/library/topology/metric-space.tex
@@ -2,6 +2,7 @@
\import{numbers.tex}
\import{function.tex}
\import{set/powerset.tex}
+\import{topology/basis.tex}
\section{Metric Spaces}
@@ -20,38 +21,42 @@
-\begin{definition}\label{induced_topology}
- $O$ is the induced topology of $d$ in $M$ iff
- $O \subseteq \pow{M}$ and
- $d$ is a metric on $M$ and
- for all $x,r,A,B,C$
- such that $x \in M$ and $r \in \reals$ and $A,B \in O$ and $C$ is a family of subsets of $O$
- we have $\openball{r}{x}{d} \in O$ and $\unions{C} \in O$ and $A \inter B \in O$.
-\end{definition}
+%\begin{definition}\label{induced_topology}
+% $O$ is the induced topology of $d$ in $M$ iff
+% $O \subseteq \pow{M}$ and
+% $d$ is a metric on $M$ and
+% for all $x,r,A,B,C$
+% such that $x \in M$ and $r \in \reals$ and $A,B \in O$ and $C$ is a family of subsets of $O$
+% we have $\openball{r}{x}{d} \in O$ and $\unions{C} \in O$ and $A \inter B \in O$.
+%\end{definition}
%\begin{definition}
% $\projcetfirst{A} = \{a \mid \exists x \in X \text{there exist $x \i } \}$
%\end{definition}
\begin{definition}\label{set_of_balls}
- $\balls{d}{M} = \{ O \in \pow{M} \mid \text{there exists $x,r$ such that $r \in \reals$ and $x \in M$ we have $O = \openball{r}{x}{d}$ } \}$.
+ $\balls{d}{M} = \{ O \in \pow{M} \mid \text{there exists $x,r$ such that $r \in \reals$ and $x \in M$ and $O = \openball{r}{x}{d}$ } \}$.
\end{definition}
-\begin{definition}\label{toindsas}
- $\metricopens{d}{M} = \{O \in \pow{M} \mid \text{
- $d$ is a metric on $M$ and
- for all $x,r,A,B,C$
- such that $x \in M$ and $r \in \reals$ and $A,B \in O$ and $C$ is a family of subsets of $O$
- we have $\openball{r}{x}{d} \in O$ and $\unions{C} \in O$ and $A \inter B \in O$.
- } \}$.
-
-\end{definition}
+%\begin{definition}\label{toindsas}
+% $\metricopens{d}{M} = \{O \in \pow{M} \mid \text{
+% $d$ is a metric on $M$ and
+% for all $x,r,A,B,C$
+% such that $x \in M$ and $r \in \reals$ and $A,B \in O$ and $C$ is a family of subsets of $O$
+% we have $\openball{r}{x}{d} \in O$ and $\unions{C} \in O$ and $A \inter B \in O$.
+% } \}$.
+%
+%\end{definition}
-\begin{theorem}\label{metric_induce_a_topology}
-
+\begin{definition}\label{metricopens}
+ $\metricopens{d}{M} = \genOpens{\balls{d}{M}}{M}$.
+\end{definition}
+\begin{theorem}
+ Let $d$ be a metric on $M$.
+ $M$ is a topological space.
\end{theorem}
@@ -70,7 +75,7 @@
\begin{enumerate}
\item \label{metric_space_metric} $\metric[M]$ is a metric on $M$.
\item \label{metric_space_topology} $M$ is a topological space.
- \item \label{metric_space_opens} for all $x \in M$ for all $r \in \reals$ $\openball{r}{x}{\metric[M]} \in \opens[M]$.
+ \item \label{metric_space_opens} $\metricopens{ \metric[M] }{M} = \opens[M]$.
\end{enumerate}
\end{struct}
@@ -132,3 +137,16 @@
% Then $\openball{r}{x}{M} \in \opens[M]$.
%\end{proposition}
+
+
+
+
+
+%TODO: - Basis indudiert topology lemma
+% - Offe Bälle sind basis
+
+% Was danach kommen soll bleibt offen, vll buch oder in proof wiki
+% Trennungsaxiom,
+
+% Notaionen aufräumen damit das gut gemercht werden kann.
+